In this paper, the first experiment of generating the phase conjugated backward wave by degenerate four-wave mixing in chlorophyll solution is reported. It is demonstrated that the efficiency converting the incident object beam into the phase conjugated backward wave with interaction length 5mm long has approached 22%. This is a four-level system having a high conversion efficiency. The intensity of the complex conjugate reflected wave is proportional to that of the incident object wave as we kept the pumping beam intensity constant. The phase conjugate behaviours of the backward wave have been demonstrated. By using the phase conjugate nature of the reflected wave, good quality reconstructed images of a grid are obtained through a phase distorting media.